Apparatus for force rounding and threading water well casing



.1 H RICE 3,180,127

APPARATUS FOR FORCE ROUNDING AND THREADING WATER WELL CASING April 27, 1965 2 Sheets-Sheet 1 Filed Aug. 27, 1962 J H RICE INVENTOR.

April 27, 1965 J H c 3,180,127

APPARATUS FOR FORCE ROUNDING AND THREADING WATER WELL CASING Filed Aug. 2'7, 1962 2 Sheets-Sheet 2 FIG.6

J H RICE INVENTOR.

United States Patent 3,180,127 APPARATUS FOR FORCE ROUNDING AND TADING WATER WELL CASING J H Rice, P.0. Box 1123, Oklahoma City, Okla. Filed Aug. 27, 1962, Ser. No. 219,641 1 Claim. (Cl. 72391) The present invention relates to water well casing and more particularly to forming threads thereon.

Water well casing is preferably formed of galvanized sheet metal wherein the ends of the casing are cold roll threaded on cooperating tapers for joining the ends of the casing. The joints comprising such casing is normally formed from sheets which are rolled and joined at their edges by a longitudinal seam and later threaded by a pair of rolling dies supported by a pair of mandrels which roll-in the threads on the end of the casing. However, water well casing, being formed of relatively thin sheet material, has a tendency to become flattened or ovate in shape and when threaded by the rolling dies still retains its ovate shape, which makes it diflicult to threadedly connect one joint of casing with another.

It is, therefore, the principal object of the instant invention to provide an apparatus and method for force rounding flattened or ovate shaped ends of water well casing and simultaneously roll thread an end portion thereof.

Another object is to provide an apparatus for force rounding overlapping adjacent end portions of Water well casing segments and connecting the two end portions of the adjacent segments.

Another object is to provide a device of this class which expands the interior of end portions of casing to form roll threads by corrugating the casing wherein the force rounded roll threaded end enhances the strength of the metal in its threaded portion and retains its circular shape after removal from the device.

Another object is to provide a device for expanding and roll threading the end of a thin walled deformable metallic tube without weakening or reducing the wall thickness thereof in the expanded portion.

Still another object is to provide a device which will roll thread consecutive joints of thin walled water well casing without subsequent splitting or fracturing the ends thereof.

The present invention accomplishes these and other objects by providing a casing supporting arbor having a mandrel movable longitudinally through the arbor. Casing gripping and expansive thread forming dies supported by one end of the mandrel are forced against the inner periphery of one end portion of the casing to be threaded by power means connected with the opposite end of the mandrel.

Other objects will be apparent from the following description when taken in conjunction with the accompanying two sheets of drawings, wherein:

FIGURE 1 is a side elevational view of the device illustrating, by dotted lines, the thread forming action;

FIGURE 2 is a right end elevational view of FIG. 1;

FIGURE 3 is a left hand elevational view of the arbor and easing clamp means;

FIGURE 4 is a fragmentary horizontal cross-sectional view taken substantially along the line 4--4 of FIG. 1;

FIGURE 5 is a view similar to FIG. 3 illustrating the thread forming action;

FIGURE 6 is a view similar to FIGS. 4 and 5 illustrating alternate dies joining end portions of two sections of casings; and,

FIGURE 7 is an elevational view of a complete section of easing formed in accordance with the present invention.

3,180,127 Patented Apr. 27, 1965 I Like characters of reference designate like parts in those figures of the drawings in which they occur.

In the drawings:

The reference numeral 10 indicates the device, as a Whole, including a frame 12; having an upright standard 14 at the rear end thereof which horizontally supports an arbor 16 intermediateits ends. The arbor 16 is centrally bored for slidably receiving an elongated mandrel 18 which projects outwardly from eachend thereof. A centrally bored frusto-conical-shaped member 20 is coaxially received by the front end portion of the mandrel 18 with the greatest diameter of the cone 20 projecting away from the arbor 16 and is held on the mandrel by a nut 22. A set of segmental roll thread forming expansive dies 24 comprising twenty-four die segments surrounds the smaller diameter end portion of the cone 20 and is positioned at its innermost end against the adjacent end of the arbor 16. The bore of the thread forming die 24 is tapered complemental to the tapered surface of the cone 20 so that the die is expanded radially when the mandrel 18 moves the cone 20 toward the arbor.

A diametrically divided circular clamp means 26, pivotally supported by the frame, supports a mating roll thread forming die 28 which snugly engages the circurnference of the adjacent end portion of a section of water well casing 30 placed over the arbor. A bushing 32 surrounds the arbor adjacent the standard 14 for centering the casing 30 while a stop 34, secured to the standard, positions the casing longitudinally of the arbor.

A rectangular cross-member or bar 36, having a central threaded aperture, is threadedly connected to the right-hand end portion of the mandrel 18, as viewed in FIG. 1 and is normally maintained in contact with the adjacent end of the arbor 16 by lock nuts 38 An air or hydraulic fluid operated cylinder 40 is vertically positioned adjacent the rearward side of the standard 14 and is pivotally connected at its depending end by links 42 to the depending end portion of the standard The piston rod 44 of the cylinder 40 projects upwardly from the cylinder and is bifurcated to form a Y-shaped member 46 with the arms thereof projecting upwardly on opposing sides of the arbor 16 and connected with a lower horizontal spring support or retainer 48.

An inverted U-shaped bracket 50, having a horizontally disposed bight portion 52, has its respective arms 53 and 54 connected to the upper end portion of the cylinder 40. A pair of spring guide rods 56 and 58 are connected at one end, respectively, to a pair of outstanding ears 60 and 62 connected with the bigh-t portion 52. The rods 56 and 58 extend upwardly through suitable apertures in the cross-member 48 and through an upper horizontal spring retainer 64. Helical springs 66 and 68 are interposed between the spring retainers 48 and 64 around the respective rods 56 andSS. Cooperating pivotally interconnected upper pairs of links or toggle joints 70 and 72 are pivotally connected at their respective ends to opposing sides of the standard 14 and to opposing ends of the cross-member 36. The pairs of links or toggle joints 70 and'72 are pivotally connected at their common central pivot point or knee to the outer side surface of the respective arms of the yoke 46 adjacent their connection with the lower spring retainer 48. Similar cooperating pivotally interconnected lower pairs of links or toggle joints 74 and 76 are similarly connected to the standard 14 and cross-member 36 and at their common central pivot point or knee to the respective ends of the bight portion 52 of the bracket 50.

Operation In operation the joint of casing 30 is placed upon the arbor 16 against the stop 34, as shown by FIG. 1. The

section .3011.

clamp 26, is closed around the adjacent end portion of the casing and the cylinder 40 is actuated to retract its piston rod 44 and yoke 46 downwardly, as viewedin FIGS. 1 and 2, whereby the toggle joints 70 and 72 force the cross-member 36 to the right, as viewed inFIG. l, which moves the mandrel18 longitudinally through the arbor. Downward movement of the yoke 46 is limited by a stop 78 secured to the depending surface of the spring retainer 48 (FIG. 2) which contacts the arbor 16 when the respective sections of the pairs of toggle joints 70 and 72 are horizontally aligned as shown by the dotted lines (FIG. 1). Simultaneously with the above action the helical springs 66 and 68 expand and lift the lower cooperating pairs of toggle joints 74 and 76 upwardly toward their dotted line position by means of the rods '56 and 58. This moves the cylinder 40 upwardly until the respective sections of the pairs of toggle joints 74 and 76 are horizontally aligned as shown by dotted lines (FIG. 1). Longitudinal movement of the mandrel 18 draws the cone member 20 into the segmented die 24 and expands the latter against the inner wall of the casing 30 which forces the latter into contact with the fixed die 28 and forcibly corrugates the end portion of the casing to form roll threads as shown by FIG. 5. After the thread forming operation, the cylinder 40 is actuated to extend its piston 44 which pivots the pairs of toggle joints 70-72 and 74-76 back toward the solid line position of FIG.l and moves the mandrel 18 forwardly through the arbor which repositions the cone member 20 outwardly of the die 24. The clamp means 26 is then opened or released and the threaded casing 30 removed from the arbor.

FIG. 6 illustrates the manner in which mating corrugating dies 80 and 82 may be positioned respectively within the clamp 26 and on the cone member 20 for force rounding and corrugating overlapped adjacent end portions of the casing 30 and an intermediate casing section 30a. As shown by FIG. 7, a-threaded casing section 30b has been connected in this manner to the casing Obviously the invention is susceptible to some change or alteration without defeating its practicability, and I therefore do not wish to be confined to the preferred embodiment shown in the drawings and described herein, further than I am limited by the scope of the appended claim.

I claim: 7

A water well casing threader, comprising: a frame; a water well casing supporting arbor supported by said frame; a mandrel slidably extending through and .projecting beyond the ends of said arbor, said mandrel having an enlarged tapered end portion with the greatest diameter thereof projecting outwardly of one end of said arbor; a segmental thread forming die comprising at least twenty-four die segments surrounding the tapered end portion of said mandrel within one end portion of a water well casing to be threaded and in end abutting coaxial relation with respect to said arbor; a thread forming mating die surrounding said segmental thread forming die segments; a bar transversely secured to the end of said mandrel opposite its tapered end portion; toggle means including upper and lower pairs of links forming toggle joints, each having a knee, extending between and connecting opposing ends of said bar to respective opposing sides of said frame; and power means for moving said mandrel longitudinally of said arbor and expanding said segmental die, said power means comprising a pressure operated cylinder having a piston rod connected with the knee of each respective said upper pair of toggle joints, a spring retainer connected with said piston rod, a guide rod extending through said spring retainer and connected, at one end, to the knee of each respective said lower pair of toggle joints, and a compression spring surrounding and connected with the other end of each respective said guide rod, whereby retraction of said piston rod into said pressure operated cylinder permits expansion of said expansion springs to apply equal and opposite forces to the knees of the respective upper and lower pairs of said toggle joints.

References fitted by the Examiner UNITED STATES PATENTS 365,621 6/87 Nettleton 153-71 859,977 7/07 Rigby l5371 XR 878,457 2/08 Deller l5380 1,753,005 4/30 Grady 15380 2,216,833 10/40 Barry 29--523 2,473,836 6/49 Wixon et al 153--73 XR 2,548,444 a 4/51 Parker et a1 153-71 2,557,722 6/51 Brauchler. 2,695,446 11/54 Meyer 29523 2,925,849 2/60 Hinz et al 15380 2,932,222 4/ Conner 153-71 XR CHARLES W. LANHAM, Primary Examiner.

WHITMORE A. WlLTZ, MICHAEL V. BRINDISI,

Examiners. 

